Why don't we do daylight savings time year round?

I understand that it’s debatable whether daylight savings time still serves a valid purpose or not, but let’s not get into that. For better or worse, we do practice daylight savings time, so therefore let’s assume it’s a good thing.

If daylight savings time is a good thing, then why don’t we do it year-round? Why not leave clocks permanently one hour ahead of the “correct” time?


The point is to shift in association with the seasonal change of dawn and sunset times. If we keep it the same, it makes it meaningless.

It already is a stupid idea, but that’s not the answer.

It was started to save fuel.

Cecil has a great article on daylight savings http://www.straightdope.com/columns/read/1079/whats-the-purpose-of-daylight-saving-time

Maybe we still do it because the farmers want that extra sunlight in the morning (if they really care about clocks)? Although I’m not sure how much farming goes on in November through March.

As I heard it,* the UK uses Daylight Savings all year round, ostensibly, to save power. The fact that this gives the little island, that holds the Greenwich meridian, instead the same local time as Europe, where much of the UK’s foreign business is conducted, is a complete and unconnected coincidence.

Disclaimer That’s just what I heard, UK dopers don’t be haters.

I am with you. Make Daylight Saving time the standard year round. I gets dark at 4 pm in December and January in the Boston area. I hate to think what happens in Canada. Screw the school kids (and I have one). Most people don’t want to leave work in the dark two months of the year. All outdoor activities come to a halt.

The UK uses GMT from October to March (?), and British Summer Time from March to October. BST is one hour ahead of GMT.

The UK is generally one hour behind continental Europe.

If you make it DST all year around, then it becomes even more arbitrary than it already is. Time (in this sense) is defined as the relation of the prime meridian to the sun. So, either pick a new meridian, or just have people change their habits. What does it matter if we work 8 to 4 instead of 9 to 5?

If you use DST all year, it’s no longer “daylight savings time”, it’s just “time”. What would be the point?

Well, it doesn’t really mater if you call it “year-round DST” or “new time zones”.

In WWII, they did that and Double DST during the summer.

You have free will - you don’t have to do what the clock tells you to do. If you want to maximize the daylight in your life, wake up at sunrise and go to bed at sunset.

Standard time has the advantage of making the available daylight symmetrical around noon. If there’s only 8 hours of daylight, it’s going to go from 8AM until 4PM. Making it 9AM until 5PM doesn’t add a second of daylight to your day, nor would making it 7AM until 3PM. It’d still be dark on the way to work, on the way home from work, or maybe even both.

Le Ministre, a crabby old bugger who hates DST.

Penn Jillette, on his video blog, suggested this, though I’m sure it’s not his idea, and has been postulated before:

Choose a standard time for the whole world - such as GMT - and everybody use that as their current time. Then in each part of the world, learn that 2100hrs is when you go to work, and 0500hrs is when you go home. The sun is still in the same place it always would be, just learn the new numbering system.

It sort of made sense when he said it.

Daylight Saving Time (not Savings) allows me to play 9 holes of golf after work in the summer. Don’t be messing with it!

I, personally, would rather work from 9 to 5, because the bars legally close at 2, so it would give me an extra hour of sleep. If I were of the type to go to the bars on weeknights. :wink:

Since I don’t really see the OP’s question being addressed, I’ll take a stab at it.

First off, standard time is set up such that the sun is at its maximum overhead point at noon at the center of the time zone. In daylight saving time, the time is shifted forward by one hour, such that local noon (at the center of the time zone) actually takes place at 1:00 p.m. So, Really Not All That Bright, if we did do DST year-round, it would not just be “time.” There would still be a distinction between daylight saving time and standard time, even if we used the former all year long.

During daylight saving time, sunset and sunrise both take place one hour later than standard time. This gives the advantage of an extra hour of daylight in the evenings, counterbalanced by one less hour of daylight in the morning. This is a good tradeoff for most people, because more people are active at sunset than at the crack of dawn, at least when the days are long, as in the summer.

Some examples will help, and will also illustrate the problem with year-round daylight saving time.

Using this website, you find that in Washington, D.C. on July 21, 2008, sunrise was at 6:00 a.m. (EDT) and sunset was at 8:29 p.m. (EDT). If we used standard time year round, sunrise on that date and location would be 5:00 a.m. (EST), and sunset would be 7:29 p.m. (EST).

(Note that EDT stands for “Eastern Daylight Time” and EST stands for “Eastern Standard Time” because Washington, D.C. is in the Eastern Time Zone.)

Anyway, this is a pretty good tradeoff for most people. You get to enjoy an extra hour of daylight after work, and who really cares whether the sun rises at 5:00 a.m. or 6:00 a.m.? Most people are asleep at either hour.

So why not use daylight saving time year round? For an answer check out the times for sunrise/sunset in winter. On December 21, 2008, in Washington, D.C., sunrise will be at 7:23 a.m. (EST) and sunset will be at 4:50 p.m. (EST). If we used daylight saving time year-round, sunset would shift to 5:50 p.m., which would make people happy, but sunrise would shift from 7:23 a.m. to 8:23 a.m.! This is unacceptable for most people. School days and work days would be starting in the dark. Kids would be walking to school in the dark.

This is why we shift our clocks twice a year. We like the advantages of DST for the summer months (with longer days), but during winter months (with shorter days), sunrise would come too late.

As to why any of this matters, Le Ministre and Balthisar, yes, people have free will, but schools and employers set the times that people have to be in attendance. People generally can’t just decide to go to school or work an hour later or earlier when they feel like it.

Makes complete sense to me.

I’ve also read that there’s a raging debate in the timekeeping community as to whether we should even attempt to peg time to the sun’s motion anymore. Some think we should stop adding leap seconds or leap years, allowing the calendar to float where it may, regardless of whether that means the winter solstice takes place on 12/21 or August 17th.

I think I meant “posited”.

Anyhoo… I think the leap second and leap year is acceptable. There’s a good reason to have seasons relatively reliably regularly spaced across the year. If it shifts by a couple of months, it will mess up a few things it doesn’t need to.

That is, if we have seasons once climate change takes hold.

DST also allows everyone to make the “decision” to change at the same time, so we don’t have your employer making a change 3 weeks before the school and 2 weeks before your spouse’s employer, and a week after your bowling league.